Description
Direct Factory Supply — Every Q235 Q345 S235JR ERW Spiral Welded Round Steel Pipe OD 10-2000mm is produced in-house with full dimensional and chemical testing before shipment.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | Q235/Q345/SS400/S235JR-S355J2 ERW Spiral Welded Round Steel Pipe |
| Product Type | ERW Spiral Welded Round Steel Pipe |
| Steel Grade | Q235, Q345, SS400, SS490, A36, A572, S235JR, S355J2 |
| Standard | JIS, ASTM, ISO 9001, CE |
| Section Shape | Round |
| Outer Diameter | 10–2000 mm |
| Length | 6 m / 6.4 m / 12 m |
| Technique | ERW / Spiral Welded |
| Surface Treatment | Hot Rolled / Cold Rolled; optional Black / Bright / Galvanized / Painted |
| Tolerance | ±1% |
| Ends | Plain / Beveled |
| Processing Service | Welding, Cutting, Bending, Punching, Decoiling |
| Application | Fluid transport, oil & gas pipelines, construction structures, hydraulic systems |
| MOQ | 1 Ton |
| Origin | Shandong, China |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Water Conservancy & Municipal | Reservoir intake/outlet pipelines, irrigation networks, municipal water supply and drainage |
| Oil & Gas | Onshore transmission pipelines, chemical fertilizer distribution lines, process piping |
| Construction & Infrastructure | Piling for bridge foundations, structural columns, scaffolding support tubes |
| Industrial & Hydraulic | Hydraulic cylinder barrels, boiler feed lines, drill pipe casings |
Where Negative Wall Tolerance Creates Structural Risk on Spiral Welded Pipe Orders
Spiral welded pipes with uncontrolled negative tolerance fail pressure tests and trigger customs rejection at destination ports.
Buyers sourcing ERW spiral welded round steel pipes often discover wall thickness deviations only after third-party inspection at the project site. A batch that measures within tolerance at the mill can arrive with cumulative negative deviation exceeding acceptable limits — especially when multiple heats are mixed in one container. The result is rejected material, delayed project timelines, and costly re-procurement. [NEED_CITE: EN 10219 dimensional tolerance requirements for structural hollow sections]
Matching Spiral Welded Pipe to Pressurized Fluid and Structural Load Applications
The OD 10–2000 mm range of Q235 Q345 S235JR ERW spiral welded round steel pipe covers both small-bore fluid distribution and large-diameter structural piling. For water supply and drainage systems, the continuous spiral forming process delivers uniform wall thickness along the full length, reducing weak points at weld intersections. For oil and gas pipelines, the combination of Q345 or S355J2 grades with 100% ultrasonic inspection on spiral seams provides the pressure resistance required for buried transmission lines. Our in-house laboratory performs chemical composition and mechanical property verification on every heat, ensuring grade consistency across multi-container orders.
Engineering Compliance and Certification Requirements for Spiral Welded Pipe
Structural applications require compliance with EN 1993 or equivalent national codes, which mandate verified mechanical properties and traceable mill test certificates. For projects in regulated markets, CE certification per EN 10219 is often a customs clearance prerequisite — missing or incorrectly referenced certificates can hold shipments at port for weeks. [NEED_CITE: CE marking requirements for structural steel under CPR regulation] Corrosive environments such as coastal piling or chemical processing demand appropriate surface treatment selection: hot-dip galvanized coating for atmospheric exposure, or painted systems with primer for buried service. The ±1% dimensional tolerance ensures fit-up compatibility with standard flanges and welding fixtures used in field assembly.
Understanding Steel Grade Selection and Spiral Welding Process for Round Pipe
The Q-series (Q235, Q345) and S-series (S235JR, S355J2) designations represent yield strength classes across Chinese GB and European EN standards, with Q345 and S355J2 offering higher load-bearing capacity for structural applications. ASTM equivalents A36 and A572 serve North American projects requiring imperial-standard compliance. The spiral welding process forms pipe from coiled strip in a continuous helical pattern, enabling large diameters up to 2000 mm from narrower strip widths — a cost advantage over longitudinal ERW for sizes above 500 mm OD. [NEED_CITE: steel grade equivalence mapping between GB, EN, and ASTM standards] Surface treatment options include hot rolled (mill scale), cold rolled (smooth finish), galvanized (zinc coating for corrosion resistance), or painted (custom color and primer systems). The choice depends on service environment: galvanized for outdoor atmospheric exposure, painted with epoxy primer for buried or submerged service.
Hidden Costs of Unverified Material and Missing Certification
Procuring ERW spiral welded round steel pipe without verified mill test certificates risks material grade substitution — Q235 shipped as Q345, or S235JR labeled without proper JR impact testing notation. When project inspectors discover grade mismatches during on-site testing, the entire batch faces rejection, requiring re-procurement and project delay. Missing CE documentation or incorrect EN standard references cause customs holds in EU and regulated markets, with demurrage costs accumulating daily. Negative tolerance beyond ±1% reduces actual load capacity below design specifications, creating structural safety concerns that only surface during pressure testing or structural loading. [NEED_CITE: material traceability requirements under EN 10204 inspection document types]
Why Source Q235 Q345 S235JR ERW Spiral Welded Round Steel Pipe From Our Factory
We operate dedicated spiral welding lines producing OD 10–2000 mm round pipe in Q235, Q345, S235JR, S355J2 and equivalent grades, covering the full diameter range from small-bore fluid lines to large structural piles. Our in-house physical and chemical laboratory performs dimensional verification, mechanical testing, and chemical composition analysis on every heat before release — mill test certificates are generated from actual test data, not copied templates. Full international certifications including ISO 9001:2015, CE (EN 10219/10210), and Singapore FPC support customs clearance in EU, Middle East, and Southeast Asian markets. Third-party inspection by SGS or BV is arranged on request, with pre-shipment photos documenting dimensional checks and surface condition. Professional container loading with anti-damage measures prevents pipe-end deformation and surface scratching during ocean transit — a critical factor for galvanized and painted finishes. Custom non-standard sizes, wall thickness, and length cutting are available with low MOQ of 1 ton per specification.
Documentation & Compliance
- Mill test certificate documenting Q235/Q345/S235JR/S355J2 chemical composition and mechanical properties per heat number
- CE certificate per EN 10219 for structural hollow sections, required for EU customs clearance
- ISO 9001:2015 quality management system certificate covering spiral welded pipe production
- SGS or BV third-party inspection report verifying dimensional tolerance and surface treatment quality
- Material traceability report linking each pipe to heat number, chemical test, and mechanical test results
- Export documentation including packing list, bill of lading, and certificate of origin for destination customs
Packaging, Loading & Delivery
- Hot rolled and cold rolled spiral welded pipes bundled with steel strips in seaworthy packaging, with end caps protecting beveled ends during transit
- Galvanized pipes packed with edge protectors and separation materials to preserve zinc coating integrity during ocean shipping
- 6 m and 12 m lengths loaded in containers with optimized nesting for OD 10–500 mm pipes, maximizing payload per shipment
- Custom cutting to project-specific lengths available, with cut ends deburred and protected against corrosion
- Heat number and steel grade stenciled on each pipe for site identification and traceability verification
- FOB, CIF, and DDP shipping terms available, with professional loading supervision and real-time tracking until destination port
Submit Specifications for Quotation and Mill Test Certificate Review
Provide your required outer diameter, wall thickness, steel grade, surface treatment, quantity, and destination port to receive a detailed quotation with unit pricing, production lead time, and shipping terms. We will include sample mill test certificates from recent production runs for your quality review, along with CE and ISO certification copies for your project documentation. For non-standard sizes or custom length requirements, our technical team will confirm feasibility and provide alternative specifications if needed.
Frequently Asked Questions
Q: What is the difference between Q345 and S355J2 steel grades for spiral welded pipe?
A: Q345 (Chinese GB standard) and S355J2 (European EN standard) are equivalent yield strength grades, both offering higher load-bearing capacity than Q235 or S235JR. The J2 designation indicates impact testing at -20°C, required for low-temperature structural applications. We provide grade equivalence documentation for projects requiring cross-standard compliance.
Q: Can you provide third-party inspection before shipment?
A: Yes, we arrange SGS or BV third-party inspection on request. The inspection covers dimensional verification, visual surface check, weld seam quality, and review of mill test certificates. Inspection is conducted after production completion and before container loading, with full photo documentation provided to the buyer.
Q: What surface treatment options are available for corrosion protection?
A: We offer hot rolled (mill scale finish), cold rolled (smooth surface), hot-dip galvanized (zinc coating for atmospheric corrosion resistance), and painted systems (primer and topcoat for buried or submerged service). Surface treatment selection depends on your service environment and project specifications.
Q: What is the minimum order quantity for custom sizes?
A: The MOQ is 1 ton per specification for standard sizes. For custom non-standard outer diameter, wall thickness, or length requirements, we will confirm minimum quantities based on production setup and material availability.
Q: How do you ensure dimensional tolerance during production?
A: Our in-house laboratory performs dimensional checks on every pipe, verifying outer diameter, wall thickness, and length against the ±1% tolerance specification. Ultrasonic testing on spiral weld seams ensures weld integrity. Full inspection reports with photos are provided before shipment for buyer review.
Request Your Quotation for Q235 Q345 S235JR ERW Spiral Welded Round Steel Pipe
Send your specifications including outer diameter, wall thickness, steel grade, surface treatment, quantity, and destination port to receive pricing and mill test certificate samples.
Shandong Xin Jiyuan Special Steel Tube Co., Ltd
Tel: +86 531 8573 6315
Mobile/WhatsApp/WeChat: +86 188 5315 7756
Email: admin@sdxjypipe.com
Address: No.11889, Jingshi West Road, Lulian Group, Jinan City, Shandong Province, China
